Treatment of hydrocarbon gases



Patented Sept. 11, 1934 UNITED STATES 1,972,926 TREATMENT OF HYDROCABBON GASES Gustav Egloff, Chicago, Ill., assignor to Universal Oil ProductsCompany, Chicago, 111., a corporation of South Dakota Application November 28, 1930, Serial No. 498,676 Claims. (01. 196-10) This invention relates to the treatment of hydyrocarbon gases and refers more particularly to the conversion of such .gases into liquid products.

More specifically the invention contemplates 5 treatment under elevated temperatures and pressures of such hydrocarbon gas mixtures as natural gases, gases occurring as the result of the cracking or pyrolysis of relatively heavy hydrocarbon oil mixtures or mixtures produced incidental to the distillation under relatively low temperature conditions of such substances as bituminous coals and shales, etc. A process is disclosed in the operations of which the influencing factors of temperature, pressure, carbon-hydrogen ratio and time are modified by the introduction of polymerizing agents at proper points with resultant increased production of liquid hydrocarbon mixtures of a substantially cyclic nature. boiling I within the range of commercial motor fuels. In the heatof polymerizing agents which cause the formation of increased yields of liquids of gasoline boiling point range and of good quality.

In a specific embodiment of the invention hydrocarbon gas mixtures are pumped through a heating element either alone or in admixture with a portion of the end product gases of the process and then passed to an enlarged reaction zone in which the reactions characteristic of the invention are promoted by the introduction of suitable polymerizing reagents, such as for example, aluminum chloride. These reagents may be introduced as atomized liquids or vapors in such a manner as to produce counter-flow conditions of treatment. The treated vapors may pass to suitable fractionating devices enabling the production of overhead and side cuts of desired boiling point ranges and reflux condensates which may be further processed in the unit employed or in other equipment. The overhead products are cooled and the condensed liquids removed to suitable storage. The fixed gases may be similarly removed or a portion may be returned to the heating element .provided with along with the raw gases charged to modify the reactions. 1

The attached drawing shows diagrammatically an arrangement of apparatus which may be used in one of many operations falling within the scope of the invention. Hydrocarbon gas mixtures maybe taken by pump or compressor 3 y from line 1 containing valve 2 and discharged through line 4 controlled by valve 5 to heating element 6 which may be a continuous arrangement of tubes suitably disposed in a furnace 7 or may be of the type of generator characteristic of water gas manufacture or any other suitable type of apparatus. Recycled gases from the process may enter line 4 from line 38. The heated gas mixture which may have been subjected to temperatures of the order of from 1400 to 1600 F. more or less in heating element 6 passes through line 8 containing valve 9 to chamber 10 in which the reactions characteristic of the process of the invention are eflected. Pump 16 indicates any suitable device for taking from line 14 containing valve 15 certain condensing or polymerizing reagents and discharging them through line 17 containing valve 18 to a point near the top of chamber 10 which may serve as a focus for their distribution counter-flow to the ascending heated vapors from line 8. As distributing means sprays, nozzles, baflles or filling materials of a generally inert nature may be employed and'the reagents may be added as vapors or sprayed in solution or in a molten condition. As examples of reagents that may be added to effect the reactions of polymerization such substances as zinc chloride, aluminum chloride, ferric chloride, etc., may be sublimed under the cond'tions of temperature and pressure obtaining and added as vapors or they may be added in concentrated aqueous or oily solutions or suspensions which are evaporated or decomposed to yield sufiicient amounts of condensing agents. Spent reagents or heavy reaction products may settle in chamber 10 and be removed through line 11 containing valve 12. Man head 13 is provided for the removal of spent masses and the cleaning of the chamber at intervals.

Pressures employed are preferably atmospheric but may be superatmospheric to a high degree if desired. Vapors leave chamber 10 through line 19 containing valve 20 which preferably permits of substantial pressure reduction prior to their passage into fractionator 21. Fractionator 21 is intermediate collecting zones 22 enabling the production of side cuts and with line 23 containing valve 24 for the removal of 110 liquid reflux condensates. Vapors of desired boil-' ing point range issuing from fractionator 21 pass through line 25 containing valve 26 to condenser 27 in which they are cooled, the partially liquefied products passing through line 28 containing valve 29 to receiver 30. This receiver is indicated as having line 35 containing valve 36 for the removal of end product liquids of the desired quality and line 31 containing valve 32 for the withdrawal of the removal of finished side cuts and line 48 containing valve 49 for the release of gases to receiver 30.

In one example of an operation falling within the scope of the invention a natural gas with a specific gravity referred to air of approximately 1.1 may be used as raw charging material. This gas mixture is heated to a temperature of 1400 F. in'the heating element under apressure of approximately 500 lbs. per square inch maintained throughout the reaction period. The vapors of aluminum chloride in amounts approximately equal to 5% by weight of the gas treated are introduced in the reaction chamber and approximately 60% of the process gases are cycled along with the natural gas fed. There is produced by this operation a yield of approximately five gallons motorfuel boiling point mixtures, these being of a completely saturated and stable nature in addition to containing only negligible amounts of sulfur, and as such are immediately utilizable for motor fuel without further chemical treatment. There is also produced a yield of one gallon per 1000 cubic feet of gas of a heavy liquidwhich when distilled under vacuum and given proper treatment yields a light lubricating oil of superior quality to the extent of 60% of the raw liquid produced.

While the foregoing example has been given as indicative of one set of results obtainable in the operation of the process of the invention it is to be understood that it is illustrative merely and in no sense to be considered as a limitation upon the broad scope of the invention.

I claim:

1. A process for producing liquid hydrocarbons from hydrocarbon gas which comprises first subjecting the gas to temperature and pressure conditions at which there is a general tendency for' the gas to yield major amounts of elementary carbon and hydrogen and minor amountsof normal 1y liquefiable compounds, then reversing the tendency of the gas to form elementary carbon and than ethane to conditions of decomposing tem-' perature and pressure at which there is a general tendency for the gas to yield major amounts of elementary carbon and hydrogen and minorv amounts of normally liquefiable compounds, then reversing the tendency of the gas to form elementary carbon and hydrogen by promptly contacting the heated gas with a polymerizing agent belonging to the group embracing zinc chloride, aluminum chloride and ferric chloride thereby forming condensible hydrocarbon vapors, and condensing the vapors thus formed.

3. A process for producing liquid hydrocarbons from hydrocarbon gas which comprises first heating the gas to a temperature of between 1400" F. and 1600 F. in a heating zone at a pressure not substantially exceeding 500 lbs. per square inch, removing the heated gas from said zone and promptly contacting the same with a polymerizing agent belonging to the group embracing zinc chloride, aluminum chloride and ferric chloride promptly contacting thesame with a polymerizing 7 agent belonging to the group embracing zinc chloride, aluminumchloride and ferric chloride thereby forming condensible vapors, and condensing the vapors thus formed.

5. The process as defined in claim 1 further characterized in that the heated gases are passed countercurrent to a stream of the polymerizing agent.

I GUSTAV EGLOFF. 

